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1.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-338447

ABSTRACT

Background: The 2020 pandemic of SARS-CoV-2 causing COVID-19 disease is an unprecedented global emergency. COVID-19 appears to be a disease with an early phase where the virus replicates, coinciding with first presentation of symptoms, followed by a later ‘inflammatory’ phase which results in severe disease in some individuals. It is known from other rapidly progressive infections such as sepsis and influenza that early treatment with antimicrobials is associated with better outcome. The hypothesis is that this holds for COVID-19 and that early antiviral treatment may prevent progression to the later phase of the disease. Methods: Trial design: Phase IIA randomised, double-blind, 2 x 2 design, placebo-controlled, interventional trial.Randomisation: Participants will be randomised 1:1 by stratification, with the following factors: age (≤ 55 vs > 55 years old), gender, obesity (BMI <30 vs ≥30), symptomatic or asymptomatic, current smoking status (Yes = current smoker, No = ex-smoker, never smoker), and presence or absence of comorbidity (defined as diabetes, hypertension, ischaemic heart disease (including previous myocardial infarction), other heart disease (arrhythmia and valvular heart disease), asthma, COPD, other chronic respiratory disease), and if the participant has or not been vaccinated.Blinding: Participants and investigators will both be blinded to treatment allocation (double-blind). Discussion: We propose to conduct a proof-of-principle placebo-controlled clinical trial of favipiravir plus or minus nitazoxanide in health workers, their household members and patients treated at the Mexican Social Security Institute (IMSS) facilities. Participants with or without symptomatic COVID-19 or tested positive will be assigned to receive favipiravir plus nitazoxanide or favipiravir plus nitazoxanide placebo. The primary outcome will be the difference in the amount of virus (‘viral load’) in the upper respiratory tract after 5 days of therapy. Secondary outcomes will include hospitalization, major morbidity and mortality, pharmacokinetics, and impact of antiviral therapy on viral genetic mutation rate. If favipiravir with nitazoxanide demonstrates important antiviral effects without significant toxicity, there will be a strong case for a larger trial in people at high risk of hospitalization or intensive care admission, for example older patients and/or those with comorbidities and with early disease Trial registration Register at Clinical Trials: NCT04918927 dated June 9 th , 2021.

2.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-338348

ABSTRACT

We investigated Favipiravir (FPV) efficacy in mild cases of COVID-19 without pneumonia and its effects towards viral clearance, clinical condition, and risk of COVID-19 pneumonia development. PCR-confirmed SARS-CoV-2-infected patients without pneumonia were enrolled (2:1) within 10 days of symptomatic onset into FPV and control arms. The former received 1800 mg FPV twice-daily (BID) on Day 1 and 800 mg BID 5-14 days thereafter until negative viral detection, while the latter received supportive care only. The primary endpoint was time to clinical improvement, which was defined by a reduced National Early Warning Score (NEWS) or score of ≤1. 62 patients (41 female) comprised the FPV arm (median age: 32 years, median BMI: 22 kg/m²) and 31 patients (19 female) comprised the control arm (median age: 28 years, median BMI: 22 kg/m². The median time to sustained clinical improvement by NEWS was 2 vs 14 days for FPV and control arms respectively (adjusted hazard ratio (aHR) of 2.77, 95% CI 1.57-4.88, P <0.001). The FPV arm also had significantly higher likelihoods of clinical improvement within 14 days after enrolment by NEWS (79% vs 32% respectively, P <0.001), particularly female patients (aOR 6.35, 95% CI 1.49-27.07, P <0.001). 8 (12.9%) and 7 (22.6%) patients in FPV and control arms developed mild pneumonia at a median (range) 6.5 (1-13) and 7 (1-13) days after treatment, respectively ( P = 0.316);all recovered well without complications. We can conclude that early treatment of FPV in symptomatic COVID-19 patients without pneumonia was associated with faster clinical improvement.

3.
Viruses ; 14(5)2022 05 11.
Article in English | MEDLINE | ID: covidwho-1869805

ABSTRACT

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) not only affects the respiratory tract but also causes neurological symptoms such as loss of smell and taste, headache, fatigue or severe cerebrovascular complications. Using transgenic mice expressing human angiotensin-converting enzyme 2 (hACE2), we investigated the spatiotemporal distribution and pathomorphological features in the CNS following intranasal infection with SARS-CoV-2 variants, as well as after prior influenza A virus infection. Apart from Omicron, we found all variants to frequently spread to and within the CNS. Infection was restricted to neurons and appeared to spread from the olfactory bulb mainly in basally oriented regions in the brain and into the spinal cord, independent of ACE2 expression and without evidence of neuronal cell death, axonal damage or demyelination. However, microglial activation, microgliosis and a mild macrophage and T cell dominated inflammatory response was consistently observed, accompanied by apoptotic death of endothelial, microglial and immune cells, without their apparent infection. Microgliosis and immune cell apoptosis indicate a potential role of microglia for pathogenesis and viral effect in COVID-19 and the possible impairment of neurological functions, especially in long COVID. These data may also be informative for the selection of therapeutic candidates and broadly support the investigation of agents with adequate penetration into relevant regions of the CNS.


Subject(s)
Angiotensin-Converting Enzyme 2 , COVID-19 , Central Nervous System , Viral Tropism , Angiotensin-Converting Enzyme 2/genetics , Animals , COVID-19/complications , Central Nervous System/physiopathology , Central Nervous System/virology , Humans , Mice , Mice, Transgenic , SARS-CoV-2/genetics
4.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-329355

ABSTRACT

Antiviral interventions are urgently required to support vaccination programmes and reduce the global burden of COVID-19. Prior to initiation of large-scale clinical trials, robust preclinical data in support of candidate plausibility are required. The speed at which preclinical models have been developed during the pandemic are unprecedented but there is a vital need for standardisation and assessment of the Critical Quality Attributes. This work provides cross-validation for the recent report demonstrating potent antiviral activity of probenecid against SARS-CoV-2 in preclinical models (1). Vero E6 cells were pre-incubated with probenecid, across a 7-point concentration range, or control media for 2 hours before infection with SARS-CoV-2 (SARS-CoV-2/Human/Liverpool/REMRQ0001/2020, Pango B;MOI 0.05). Probenecid or control media was then reapplied and plates incubated for 48 hours. Cells were fixed with 4% v/v paraformaldehyde, stained with crystal violet and cytopathic activity quantified by spectrophotometry at 590 nm. Syrian golden hamsters (n=5 per group) were intranasally inoculated with virus (SARS-CoV-2 Delta variant B.1.617.2;103 PFU/hamster) for 24 hours prior to treatment. Hamsters were treated with probenecid or vehicle for 4 doses. Hamsters were ethically euthanised before quantification of total and sub-genomic pulmonary viral RNAs. No inhibition of cytopathic activity was observed for probenecid at any concentration in Vero E6 cells. Furthermore, no reduction in either total or sub-genomic RNA was observed in terminal lung samples from hamsters on day 3 (P > 0.05). Body weight of uninfected hamsters remained stable throughout the course of the experiment whereas both probenecid- (6 - 9% over 3 days) and vehicle-treated (5 - 10% over 3 days) infected hamsters lost body weight which was comparable in magnitude (P > 0.5). The presented data do not support probenecid as a SARS-CoV-2 antiviral. These data do not support use of probenecid in COVID-19 and further analysis is required prior to initiation of clinical trials to investigate the potential utility of this drug.

5.
EuropePMC;
Preprint in English | EuropePMC | ID: ppcovidwho-327398

ABSTRACT

Summary Background Finding: effective therapeutics for COVID-19 continues to be an urgent need, especially considering use context limitations and high cost of currently approved agents. The NACOVID trial investigated the efficacy and safety of repurposed antiprotozoal and antiretroviral drugs, nitazoxanide and atazanavir/ritonavir, used in combination for COVID-19. Methods In this pilot, randomized, open-label trial conducted in Nigeria, patients diagnosed with mild to moderate COVID-19 were randomly assigned to receive standard of care (SoC) or SoC plus a 14-day course of nitazoxanide (1000 mg b.i.d.) and atazanavir/ritonavir (300/100 mg od) and followed through day 28. Study endpoints included time to clinical improvement, SARS-CoV-2 viral load change, and time to complete symptom resolution. Safety and pharmacokinetics of nitazoxanide active metabolite, tizoxanide, were also evaluated. This trial was registered with ClinicalTrials.gov ( NCT04459286 ). Findings There was no difference in time to clinical improvement between the SoC (n = 26) and SoC plus intervention arms (n = 31;Cox proportional hazards regression analysis adjusted hazard ratio, aHR = 0.898, 95% CI: 0.492-1.638, p = 0.725). No difference was observed in the pattern of saliva SARS-CoV-2 viral load changes from days 2 to 28 in the 35% of patients with detectable virus at baseline (20/57) between the two arms (aHR = 0.948, 95% CI: 0.341-2.636, p = 0.919). There was no significant difference in time from enrolment to complete symptom resolution (aHR = 0.535, 95% CI: 0.251 - 1.140, p = 0.105). Atazanavir/ritonavir increased tizoxanide plasma exposure by 68% and median trough plasma concentration was 1546 ng/ml (95% CI: 797-2557), above its putative EC 90 in 54% of patients. Tizoxanide was not detectable in saliva. Interpretation These findings should be interpreted in the context of incomplete enrolment (64%) and the limited number of patients with detectable SARS-CoV-2 in saliva at baseline in this trial. Funding The University of Liverpool. Research in context Evidence before this study The potential efficacy of nitazoxanide as a repurposed drug for COVID-19 is being investigated in a number of studies due to confirmed in vitro activity against SARS-CoV-2. Available data from completed randomised controlled trials in which clinical improvement, effect on viral load, and symptom resolution were evaluated as outcomes do not offer conclusive evidence. Added value of this study In the NACOVID trial, we sought to take advantage of a model-informed strategy and known interaction between nitazoxanide and atazanavir/ritonavir to achieve optimal concentration of tizoxanide in plasma, and possibly in respiratory tracts of patients with mild to moderate COVID-19. While this strategy significantly enhanced tizoxanide exposure in the plasma of patients, our data indicated poor penetration into the respiratory tracts. Specifically, there were no differences in time to clinical improvement, viral load changes, and symptom resolutions between patients who were given standard of care alone and those who combined it with study intervention. Implications of all the available evidence The clinical benefit of nitazoxanide remains uncertain. The present study highlights the need for early insight into target site biodistribution of potential COVID-19 therapeutics to better inform candidate selection for clinical trials.

6.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-318197

ABSTRACT

Backgrounds: urvival following out-of-hospital cardiac arrest is worse in the United Kingdom than in many other developed countries, possibly due to below average delivery of early bystander cardiopulmonary resuscitation (CPR). Training laypeople how to perform CPR is vital, but skill decays quickly. Most methods of training require face-to-face contact which is challenging during the Covid-19 pandemic. The optimal method of delivering CPR refresher training is not yet known. Our aim was to understand how basic life support (BLS) performance decays over time, and how best to deliver refresher training in terms of timeframe and training method – are methods with limited instructor / student contact effective? Methods: this quasi-randomised trial allocated participants to receive refresher training one, two, or three years after their initial BLS training. Participants’ baseline BLS performance was assessed by a trained instructor, and then they were randomly allocated to receive refresher training via one of three methods: one-to-one instructor led training, video assisted learning with self-directed practice, or a written information guide alone. BLS performance was assessed again following refresher training. Results: 42 participants were recruited - all completed all study stages. Baseline BLS performance was poor – only 21% of participants passed a formative assessment. Students who had received BLS training most recently showed better BLS performance than those where greater time had elapsed. one-to-one training was the most effective refresher training modality, and video assisted training did not lead to significant improvement in BLS performance. Conclusion: one-to-one BLS refresher training outperforms self-directed methods with more limited instructor contact, though it requires greater resource and planning. It may be impractical to deliver instructor-led BLS refresher training during the Covid-19 pandemic. The video we chose to use for our training was not interactive, though such tools exist. Alternative video-led approaches (with or without instructor guidance) should be explored to investigate if they are more effective than the tool we used in this study.

7.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-312807

ABSTRACT

SARS-CoV-2 remains a global threat to human health particularly as escape mutants emerge. There is an unmet need for effective treatments against COVID-19 for which neutralizing single domain antibodies (nanobodies) have significant potential. Their small size and stability mean that nanobodies are compatible with respiratory administration. We report four nanobodies (C5, H3, C1, F2) engineered as homotrimers with pmolar affinity for the receptor binding domain (RBD) of the SARS-CoV-2 spike protein. Crystal structures show C5 and H3 overlap the ACE2 epitope, whilst C1 and F2 bind to a different epitope. Cryo Electron Microscopy shows C5 binding results in an all down arrangement of the Spike protein. C1, H3 and C5 all neutralize the Victoria strain, and the highly transmissible Alpha (B.1.1.7 first identified in Kent, UK) strain and C1 also neutralizes the Beta (B.1.35, first identified in South Africa). Administration of C5-trimer via the respiratory route showed potent therapeutic efficacy in the Syrian hamster model of COVID-19 and separately effective prophylaxis. The molecule was similarly potent by intraperitoneal injection.

8.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-312419

ABSTRACT

The spread of SARS-CoV-2 across the world requires the formation of a range of interventions that include immunomodulatory or antiviral therapeutics and repurposing of existing drug compounds is an important strategy to rapidly identify possible options. Niclosamide is a cheap and generic drug compound with a proven in vitro ability to inhibit viral replication of SARS-CoV-2;this drug also has known poor oral bioavailability due to very low water solubility. Here, we demonstrate the nanoparticle formulation of niclosamide using a new, cheap and scalable process to enable long-acting injectable administration and show extended circulating drug exposure in vivo over 28 days using a rodent model after depot injection.

9.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-311524

ABSTRACT

Background: There is an urgent unmet clinical need for the identification of novel therapeutics for the treatment of COVID-19. A number of COVID-19 late phase trial platforms have been developed to investigate (often repurposed) drugs both in the UK and globally (e.g. RECOVERY led by the University of Oxford and SOLIDARITY led by WHO). There is a pressing need to investigate novel candidates within early phase trial platforms, from which promising candidates can feed into established later phase platforms. AGILE grew from a UK-wide collaboration to undertake early stage clinical evaluation of candidates for SARS-CoV-2 infection to accelerate national and global healthcare interventions. Methods: /Design: AGILE is a seamless phase I/IIa platform study to establish the optimum dose, determine the activity and safety of each candidate and recommend whether it should be evaluated further. Each candidate is evaluated in its own trial, either as an open label single arm healthy volunteer study or in patients, randomising between candidate and control usually in a 2:1 allocation in favour of the candidate. Each dose is assessed sequentially for safety usually in cohorts of 6 patients. Once a phase II dose has been identified, efficacy is assessed by seamlessly expanding into a larger cohort. AGILE is completely flexible in that the core design in the master protocol can be adapted for each candidate based on prior knowledge of the candidate (i.e. population, primary endpoint and sample size can be amended). This information is detailed in each candidate specific trial protocol of the master protocol. Discussion: Few approved treatments for COVID-19 are available such as dexamethasone, remdesivir and tociluzimab in hospitalised patients. The AGILE platform aims to rapidly identify new efficacious and safe treatments to help end the current global COVID-19 pandemic. We currently have three candidate specific trials within this platform study that are open to recruitment. Trial registrations: EudraCT Number: 2020-001860-27 14th March 2020 ClinicalTrials.gov Identifier: NCT04746183ISRCTN reference: 27106947

10.
Viruses ; 14(2)2022 02 11.
Article in English | MEDLINE | ID: covidwho-1687050

ABSTRACT

Despite the development of specific therapies against severe acute respiratory coronavirus 2 (SARS-CoV-2), the continuous investigation of the mechanism of action of clinically approved drugs could provide new information on the druggable steps of virus-host interaction. For example, chloroquine (CQ)/hydroxychloroquine (HCQ) lacks in vitro activity against SARS-CoV-2 in TMPRSS2-expressing cells, such as human pneumocyte cell line Calu-3, and likewise, failed to show clinical benefit in the Solidarity and Recovery clinical trials. Another antimalarial drug, mefloquine, which is not a 4-aminoquinoline like CQ/HCQ, has emerged as a potential anti-SARS-CoV-2 antiviral in vitro and has also been previously repurposed for respiratory diseases. Here, we investigated the anti-SARS-CoV-2 mechanism of action of mefloquine in cells relevant for the physiopathology of COVID-19, such as Calu-3 cells (that recapitulate type II pneumocytes) and monocytes. Molecular pathways modulated by mefloquine were assessed by differential expression analysis, and confirmed by biological assays. A PBPK model was developed to assess mefloquine's optimal doses for achieving therapeutic concentrations. Mefloquine inhibited SARS-CoV-2 replication in Calu-3, with an EC50 of 1.2 µM and EC90 of 5.3 µM. It reduced SARS-CoV-2 RNA levels in monocytes and prevented virus-induced enhancement of IL-6 and TNF-α. Mefloquine reduced SARS-CoV-2 entry and synergized with Remdesivir. Mefloquine's pharmacological parameters are consistent with its plasma exposure in humans and its tissue-to-plasma predicted coefficient points suggesting that mefloquine may accumulate in the lungs. Altogether, our data indicate that mefloquine's chemical structure could represent an orally available host-acting agent to inhibit virus entry.


Subject(s)
Alveolar Epithelial Cells/drug effects , Antiviral Agents/pharmacology , Chloroquine/pharmacology , Mefloquine/pharmacology , SARS-CoV-2/drug effects , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/pharmacology , Alanine/analogs & derivatives , Alanine/pharmacology , Alveolar Epithelial Cells/virology , COVID-19/drug therapy , Cell Line , Drug Repositioning/methods , Humans , Serine Endopeptidases/genetics , Virus Internalization/drug effects
11.
EBioMedicine ; 76: 103856, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1676708

ABSTRACT

BACKGROUND: Many repurposed drugs have progressed rapidly to Phase 2 and 3 trials in COVID19 without characterisation of Pharmacokinetics /Pharmacodynamics including safety data. One such drug is nafamostat mesylate. METHODS: We present the findings of a phase Ib/IIa open label, platform randomised controlled trial of intravenous nafamostat in hospitalised patients with confirmed COVID-19 pneumonitis. Patients were assigned randomly to standard of care (SoC), nafamostat or an alternative therapy. Nafamostat was administered as an intravenous infusion at a dose of 0.2 mg/kg/h for a maximum of seven days. The analysis population included those who received any dose of the trial drug and all patients randomised to SoC. The primary outcomes of our trial were the safety and tolerability of intravenous nafamostat as an add on therapy for patients hospitalised with COVID-19 pneumonitis. FINDINGS: Data is reported from 42 patients, 21 of which were randomly assigned to receive intravenous nafamostat. 86% of nafamostat-treated patients experienced at least one AE compared to 57% of the SoC group. The nafamostat group were significantly more likely to experience at least one AE (posterior mean odds ratio 5.17, 95% credible interval (CI) 1.10 - 26.05) and developed significantly higher plasma creatinine levels (posterior mean difference 10.57 micromol/L, 95% CI 2.43-18.92). An average longer hospital stay was observed in nafamostat patients, alongside a lower rate of oxygen free days (rate ratio 0.55-95% CI 0.31-0.99, respectively). There were no other statistically significant differences in endpoints between nafamostat and SoC. PK data demonstrated that intravenous nafamostat was rapidly broken down to inactive metabolites. We observed no significant anticoagulant effects in thromboelastometry. INTERPRETATION: In hospitalised patients with COVID-19, we did not observe evidence of anti-inflammatory, anticoagulant or antiviral activity with intravenous nafamostat, and there were additional adverse events. FUNDING: DEFINE was funded by LifeArc (an independent medical research charity) under the STOPCOVID award to the University of Edinburgh. We also thank the Oxford University COVID-19 Research Response Fund (BRD00230).


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Benzamidines/therapeutic use , COVID-19/drug therapy , Guanidines/therapeutic use , Administration, Intravenous , Adult , Aged , Aged, 80 and over , Anti-Inflammatory Agents, Non-Steroidal/pharmacokinetics , Benzamidines/adverse effects , Benzamidines/pharmacokinetics , Biomarkers/blood , Biomarkers/metabolism , COVID-19/mortality , COVID-19/virology , Drug Administration Schedule , Female , Guanidines/adverse effects , Guanidines/pharmacokinetics , Half-Life , Humans , Immunophenotyping , Kaplan-Meier Estimate , Male , Middle Aged , SARS-CoV-2/isolation & purification , SARS-CoV-2/physiology , Treatment Outcome , Viral Load
12.
Int J Antimicrob Agents ; 59(3): 106542, 2022 Mar.
Article in English | MEDLINE | ID: covidwho-1654507

ABSTRACT

A key element for the prevention and management of coronavirus disease 2019 is the development of effective therapeutics. Drug combination strategies offer several advantages over monotherapies. They have the potential to achieve greater efficacy, to increase the therapeutic index of drugs and to reduce the emergence of drug resistance. We assessed the in vitro synergistic interaction between remdesivir and ivermectin, both approved by the US Food and Drug Administration, and demonstrated enhanced antiviral activity against severe acute respiratory syndrome coronavirus-2. Whilst the in vitro synergistic activity reported here does not support the clinical application of this combination treatment strategy due to insufficient exposure of ivermectin in vivo, the data do warrant further investigation. Efforts to define the mechanisms underpinning the observed synergistic action could lead to the development of novel treatment strategies.


Subject(s)
COVID-19 , SARS-CoV-2 , Adenosine Monophosphate/analogs & derivatives , Alanine/analogs & derivatives , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , COVID-19/drug therapy , Humans , Ivermectin/pharmacology , Ivermectin/therapeutic use
13.
SSRN; 2021.
Preprint in English | SSRN | ID: ppcovidwho-292030

ABSTRACT

Background: Many repurposed drugs have progressed rapidly to Phase 2 and 3 trials in COVID19 without characterisation of Pharmacokinetics /Pharmacodynamics including safety data. One such drug is Nafamostat Mesylate. Methods: We present the findings of a phase Ib/II open label, platform randomised controlled trial of intravenous Nafamostat in hospitalised patients with confirmed COVID-19 pneumonitis. Patients were assigned randomly to standard of care (SoC), Nafamostat or an alternative therapy. Nafamostat was administered as an intravenous infusion at a dose of 0.2mg/kg/hour for a maximum of seven days. The analysis population included those who received any dose of the trial drug and all patients randomised to SoC. Results: Data is reported from 42 patients, 21 of which were randomly assigned to receive intravenous Nafamostat. 78% of Nafamostat-treated patients experienced at least one AE compared to 57% of the SoC group. The Nafamostat group developed significantly higher plasma creatinine levels and had a lower number of oxygen free days (posterior mean difference 10.57 micromol/L, 95% HPD interval 2.43 - 18.92, rate ratio 0.55- 95% HPD interval 0.31- 0.99 respectively). There were no other statistically significant differences in endpoints between Nafamostat and SoC. PK data demonstrated that intravenous Nafamostat was rapidly broken down to inactive metabolites. We observed no significant anticoagulant effects in thromboelastometry. Participants in the Nafamostat group had higher D-Dimers. Interpretation: In hospitalised patients with COVID-19, we did not observe evidence of anti-inflammatory, anticoagulant or antiviral activity with intravenous Nafamostat. Further evaluation of Nafamostat delivered via a different route may be warranted. Clinical Trial Registration Details: This trial has been registered on ISRCTN (https://www.isrctn.com/) ISRCTN14212905, and Clinicaltrials.gov (https://www.clinicaltrials.gov/) NCT04473053. Funding Information: DEFINE was funded by LifeArc (an independent medical research charity under the STOPCOVID award to the University of Edinburgh. We also thank the Oxford University COVID-19 Research Response Fund (BRD00230). Declaration of Interests: The authors report no conflict of interests. Ethics Approval Statement: The DEFINE trial has received full ethical approval from Scotland A REC (20/SS/0066), the MHRA (EudraCT 2020-002230-32) and NHS Lothian. Written informed consent was taken by trial clinicians prior to any trial procedures being performed. If a patient lacked capacity, consent could be provided by their next of kin.

14.
Clin Pharmacol Ther ; 111(3): 585-594, 2022 03.
Article in English | MEDLINE | ID: covidwho-1482119

ABSTRACT

Repurposing approved drugs may rapidly establish effective interventions during a public health crisis. This has yielded immunomodulatory treatments for severe coronavirus disease 2019 (COVID-19), but repurposed antivirals have not been successful to date because of redundancy of the target in vivo or suboptimal exposures at studied doses. Nitazoxanide is a US Food and Drug Administration (FDA) approved antiparasitic medicine, that physiologically-based pharmacokinetic (PBPK) modeling has indicated may provide antiviral concentrations across the dosing interval, when repurposed at higher than approved doses. Within the AGILE trial platform (NCT04746183) an open label, adaptive, phase I trial in healthy adult participants was undertaken with high-dose nitazoxanide. Participants received 1,500 mg nitazoxanide orally twice-daily with food for 7 days. Primary outcomes were safety, tolerability, optimum dose, and schedule. Intensive pharmacokinetic (PK) sampling was undertaken day 1 and 5 with minimum concentration (Cmin ) sampling on days 3 and 7. Fourteen healthy participants were enrolled between February 18 and May 11, 2021. All 14 doses were completed by 10 of 14 participants. Nitazoxanide was safe and with no significant adverse events. Moderate gastrointestinal disturbance (loose stools or diarrhea) occurred in 8 participants (57.1%), with urine and sclera discoloration in 12 (85.7%) and 9 (64.3%) participants, respectively, without clinically significant bilirubin elevation. This was self-limiting and resolved upon drug discontinuation. PBPK predictions were confirmed on day 1 but with underprediction at day 5. Median Cmin was above the in vitro target concentration on the first dose and maintained throughout. Nitazoxanide administered at 1,500 mg b.i.d. with food was safe with acceptable tolerability a phase Ib/IIa study is now being initiated in patients with COVID-19.


Subject(s)
Antiviral Agents/administration & dosage , Nitro Compounds/administration & dosage , Nitro Compounds/adverse effects , Nitro Compounds/pharmacokinetics , Thiazoles/administration & dosage , Thiazoles/adverse effects , Thiazoles/pharmacokinetics , Adult , Antiviral Agents/adverse effects , Antiviral Agents/pharmacokinetics , COVID-19/drug therapy , Drug Repositioning , Female , Healthy Volunteers , Humans , Male , Middle Aged , Young Adult
15.
Nat Commun ; 12(1): 5469, 2021 09 22.
Article in English | MEDLINE | ID: covidwho-1434103

ABSTRACT

SARS-CoV-2 remains a global threat to human health particularly as escape mutants emerge. There is an unmet need for effective treatments against COVID-19 for which neutralizing single domain antibodies (nanobodies) have significant potential. Their small size and stability mean that nanobodies are compatible with respiratory administration. We report four nanobodies (C5, H3, C1, F2) engineered as homotrimers with pmolar affinity for the receptor binding domain (RBD) of the SARS-CoV-2 spike protein. Crystal structures show C5 and H3 overlap the ACE2 epitope, whilst C1 and F2 bind to a different epitope. Cryo Electron Microscopy shows C5 binding results in an all down arrangement of the Spike protein. C1, H3 and C5 all neutralize the Victoria strain, and the highly transmissible Alpha (B.1.1.7 first identified in Kent, UK) strain and C1 also neutralizes the Beta (B.1.35, first identified in South Africa). Administration of C5-trimer via the respiratory route showed potent therapeutic efficacy in the Syrian hamster model of COVID-19 and separately, effective prophylaxis. The molecule was similarly potent by intraperitoneal injection.


Subject(s)
Antibodies, Neutralizing/pharmacology , COVID-19/drug therapy , Single-Domain Antibodies/pharmacology , Spike Glycoprotein, Coronavirus/metabolism , Administration, Intranasal , Animals , Antibodies, Neutralizing/administration & dosage , Antibodies, Neutralizing/genetics , Antibodies, Neutralizing/immunology , Cryoelectron Microscopy , Crystallography, X-Ray , Disease Models, Animal , Dose-Response Relationship, Immunologic , Epitopes/chemistry , Epitopes/metabolism , Female , Male , Mesocricetus , Neutralization Tests , SARS-CoV-2/drug effects , Single-Domain Antibodies/administration & dosage , Single-Domain Antibodies/immunology , Single-Domain Antibodies/metabolism , Spike Glycoprotein, Coronavirus/chemistry
16.
Clin Pharmacol Ther ; 108(4): 775-790, 2020 10.
Article in English | MEDLINE | ID: covidwho-1384148

ABSTRACT

There is a rapidly expanding literature on the in vitro antiviral activity of drugs that may be repurposed for therapy or chemoprophylaxis against severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2). However, this has not been accompanied by a comprehensive evaluation of the target plasma and lung concentrations of these drugs following approved dosing in humans. Accordingly, concentration 90% (EC90 ) values recalculated from in vitro anti-SARS-CoV-2 activity data was expressed as a ratio to the achievable maximum plasma concentration (Cmax ) at an approved dose in humans (Cmax /EC90 ratio). Only 14 of the 56 analyzed drugs achieved a Cmax /EC90 ratio above 1. A more in-depth assessment demonstrated that only nitazoxanide, nelfinavir, tipranavir (ritonavir-boosted), and sulfadoxine achieved plasma concentrations above their reported anti-SARS-CoV-2 activity across their entire approved dosing interval. An unbound lung to plasma tissue partition coefficient (Kp Ulung ) was also simulated to derive a lung Cmax /half-maximal effective concentration (EC50 ) as a better indicator of potential human efficacy. Hydroxychloroquine, chloroquine, mefloquine, atazanavir (ritonavir-boosted), tipranavir (ritonavir-boosted), ivermectin, azithromycin, and lopinavir (ritonavir-boosted) were all predicted to achieve lung concentrations over 10-fold higher than their reported EC50 . Nitazoxanide and sulfadoxine also exceeded their reported EC50 by 7.8-fold and 1.5-fold in lung, respectively. This analysis may be used to select potential candidates for further clinical testing, while deprioritizing compounds unlikely to attain target concentrations for antiviral activity. Future studies should focus on EC90 values and discuss findings in the context of achievable exposures in humans, especially within target compartments, such as the lungs, in order to maximize the potential for success of proposed human clinical trials.


Subject(s)
Antiviral Agents/administration & dosage , Betacoronavirus/drug effects , Coronavirus Infections/drug therapy , Drug Delivery Systems/methods , Drug Repositioning/methods , Pneumonia, Viral/drug therapy , Antiviral Agents/blood , COVID-19 , Coronavirus Infections/blood , Humans , Pandemics , Pneumonia, Viral/blood , SARS-CoV-2
17.
J Antimicrob Chemother ; 76(12): 3286-3295, 2021 11 12.
Article in English | MEDLINE | ID: covidwho-1376308

ABSTRACT

OBJECTIVES: AGILE is a Phase Ib/IIa platform for rapidly evaluating COVID-19 treatments. In this trial (NCT04746183) we evaluated the safety and optimal dose of molnupiravir in participants with early symptomatic infection. METHODS: We undertook a dose-escalating, open-label, randomized-controlled (standard-of-care) Bayesian adaptive Phase I trial at the Royal Liverpool and Broadgreen Clinical Research Facility. Participants (adult outpatients with PCR-confirmed SARS-CoV-2 infection within 5 days of symptom onset) were randomized 2:1 in groups of 6 participants to 300, 600 and 800 mg doses of molnupiravir orally, twice daily for 5 days or control. A dose was judged unsafe if the probability of 30% or greater dose-limiting toxicity (the primary outcome) over controls was 25% or greater. Secondary outcomes included safety, clinical progression, pharmacokinetics and virological responses. RESULTS: Of 103 participants screened, 18 participants were enrolled between 17 July and 30 October 2020. Molnupiravir was well tolerated at 300, 600 and 800 mg doses with no serious or severe adverse events. Overall, 4 of 4 (100%), 4 of 4 (100%) and 1 of 4 (25%) of the participants receiving 300, 600 and 800 mg molnupiravir, respectively, and 5 of 6 (83%) controls, had at least one adverse event, all of which were mild (≤grade 2). The probability of ≥30% excess toxicity over controls at 800 mg was estimated at 0.9%. CONCLUSIONS: Molnupiravir was safe and well tolerated; a dose of 800 mg twice daily for 5 days was recommended for Phase II evaluation.


Subject(s)
COVID-19 , SARS-CoV-2 , Adult , Bayes Theorem , Humans , Research Design , Treatment Outcome
18.
FEBS Lett ; 595(18): 2323-2340, 2021 09.
Article in English | MEDLINE | ID: covidwho-1332924

ABSTRACT

The COVID-19 pandemic, caused by the SARS-CoV-2 coronavirus, has triggered a worldwide health emergency. Here, we show that ferritin-like Dps from hyperthermophilic Sulfolobus islandicus, covalently coupled with SARS-CoV-2 antigens via the SpyCatcher system, forms stable multivalent dodecameric vaccine nanoparticles that remain intact even after lyophilisation. Immunisation experiments in mice demonstrated that the SARS-CoV-2 receptor binding domain (RBD) coupled to Dps (RBD-S-Dps) elicited a higher antibody titre and an enhanced neutralising antibody response compared to monomeric RBD. A single immunisation with RBD-S-Dps completely protected hACE2-expressing mice from serious illness and led to viral clearance from the lungs upon SARS-CoV-2 infection. Our data highlight that multimerised SARS-CoV-2 subunit vaccines are a highly efficacious modality, particularly when combined with an ultra-stable scaffold.


Subject(s)
Angiotensin-Converting Enzyme 2/immunology , COVID-19 Vaccines/immunology , COVID-19/prevention & control , Receptors, Virus/immunology , Spike Glycoprotein, Coronavirus/immunology , Animals , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Bacterial Proteins/chemistry , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/chemistry , DNA-Binding Proteins/chemistry , Ferritins/chemistry , Humans , Immunization , Mice , Nanoparticles , Protein Domains , Protein Multimerization , Spike Glycoprotein, Coronavirus/chemistry , Sulfolobus
19.
Trials ; 22(1): 487, 2021 Jul 26.
Article in English | MEDLINE | ID: covidwho-1327946

ABSTRACT

BACKGROUND: There is an urgent unmet clinical need for the identification of novel therapeutics for the treatment of COVID-19. A number of COVID-19 late phase trial platforms have been developed to investigate (often repurposed) drugs both in the UK and globally (e.g. RECOVERY led by the University of Oxford and SOLIDARITY led by WHO). There is a pressing need to investigate novel candidates within early phase trial platforms, from which promising candidates can feed into established later phase platforms. AGILE grew from a UK-wide collaboration to undertake early stage clinical evaluation of candidates for SARS-CoV-2 infection to accelerate national and global healthcare interventions. METHODS/DESIGN: AGILE is a seamless phase I/IIa platform study to establish the optimum dose, determine the activity and safety of each candidate and recommend whether it should be evaluated further. Each candidate is evaluated in its own trial, either as an open label single arm healthy volunteer study or in patients, randomising between candidate and control usually in a 2:1 allocation in favour of the candidate. Each dose is assessed sequentially for safety usually in cohorts of 6 patients. Once a phase II dose has been identified, efficacy is assessed by seamlessly expanding into a larger cohort. AGILE is completely flexible in that the core design in the master protocol can be adapted for each candidate based on prior knowledge of the candidate (i.e. population, primary endpoint and sample size can be amended). This information is detailed in each candidate specific trial protocol of the master protocol. DISCUSSION: Few approved treatments for COVID-19 are available such as dexamethasone, remdesivir and tocilizumab in hospitalised patients. The AGILE platform aims to rapidly identify new efficacious and safe treatments to help end the current global COVID-19 pandemic. We currently have three candidate specific trials within this platform study that are open to recruitment. TRIAL REGISTRATION: EudraCT Number: 2020-001860-27 14 March 2020 ClinicalTrials.gov Identifier: NCT04746183  19 February 2021 ISRCTN reference: 27106947.


Subject(s)
COVID-19 , Pandemics , Cohort Studies , Humans , SARS-CoV-2 , Treatment Outcome
20.
Adv Drug Deliv Rev ; 178: 113848, 2021 11.
Article in English | MEDLINE | ID: covidwho-1283843

ABSTRACT

The emergence of SARS-CoV-2, and the ensuing global pandemic, has resulted in an unprecedented response to identify therapies that can limit uncontrolled inflammation observed in patients with moderate to severe COVID-19. The immune pathology behind COVID-19 is complex and involves the activation and interaction of multiple systems including, but not limited to, complement, inflammasomes, endothelial as well as innate and adaptive immune cells to bring about a convoluted profile of inflammation, coagulation and tissue damage. To date, therapeutic approaches have focussed on inhibition of coagulation, untargeted immune suppression and/or cytokine-directed blocking agents. Regardless of recently achieved improvements in individual patient outcomes and survival rates, improved and focussed approaches targeting individual systems involved is needed to further improve prognosis and wellbeing. This review summarizes the current understanding of molecular and cellular systems involved in the pathophysiology of COVID-19, and their contribution to pathogen clearance and damage to then discuss possible therapeutic options involving immunomodulatory drug delivery systems as well as summarising the complex interplay between them.


Subject(s)
Antiviral Agents/administration & dosage , COVID-19/drug therapy , Drug Delivery Systems/methods , Immunologic Factors/administration & dosage , Inflammasomes/antagonists & inhibitors , Adjuvants, Immunologic/administration & dosage , Animals , Antiviral Agents/immunology , COVID-19/immunology , Communicable Diseases/drug therapy , Communicable Diseases/immunology , Complement Activation/drug effects , Complement Activation/immunology , Drug Delivery Systems/trends , Humans , Immunologic Factors/immunology , Inflammasomes/immunology
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